1. Field of the Invention
The present invention relates to a detection apparatus detecting the positions of predetermined locations of a member to be detected using a plurality of sensors.
2. Description of the Related Art
There are well-known detection apparatus which detect predetermined positions of a rotating or linearly moving member to control, for example, the stopping of the member.
Such a detection apparatus includes a sensor and detects the position of a member when the sensor reacts to a predetermined pattern formed on the member. As a result, various processes can be carried out including controlling the member to stop it in a detected position of the member. The detected position may be a position at a certain angle of rotation in the case of a rotating member. In the case of a member in a linear movement, the detected position may be a certain position of the member in the longitudinal direction thereof.
When positions are detected as thus described, the greater the number (n) of sensors are used, the greater the number of positions to be detected. In general, a sensor output is a binary output which assumes, for example, a value “1” indicating detection or a value “0” indicating non-detection. When a unique pattern to be detected is provided in association with each of n sensors, n rows of such patterns must be provided as patterns to be detected by the n sensors which acquire arbitrary positions. Therefore, it is necessary to form 2n patterns in total.